package com.lingx.gt06.server.utils;
import sun.misc.CRC16;

public class CRCUtil {
private static final byte[] hex = "0123456789ABCDEF".getBytes();

public static String getCRC16( byte[] data){
int CRCTABLE[]={
   0xF078,0xE1F1,0xD36A,0xC2E3,0xB65C,0xA7D5,0x954E,0x84C7,
   0x7C30,0x6DB9,0x5F22,0x4EAB,0x3A14,0x2B9D,0x1906,0x088F,
   0xE0F9,0xF170,0xC3EB,0xD262,0xA6DD,0xB754,0x85CF,0x9446,
   0x6CB1,0x7D38,0x4FA3,0x5E2A,0x2A95,0x3B1C,0x0987,0x180E,
   0xD17A,0xC0F3,0xF268,0xE3E1,0x975E,0x86D7,0xB44C,0xA5C5,
   0x5D32,0x4CBB,0x7E20,0x6FA9,0x1B16,0x0A9F,0x3804,0x298D,
   0xC1FB,0xD072,0xE2E9,0xF360,0x87DF,0x9656,0xA4CD,0xB544,
   0x4DB3,0x5C3A,0x6EA1,0x7F28,0x0B97,0x1A1E,0x2885,0x390C,
   0xB27C,0xA3F5,0x916E,0x80E7,0xF458,0xE5D1,0xD74A,0xC6C3,
   0x3E34,0x2FBD,0x1D26,0x0CAF,0x7810,0x6999,0x5B02,0x4A8B,
   0xA2FD,0xB374,0x81EF,0x9066,0xE4D9,0xF550,0xC7CB,0xD642,
   0x2EB5,0x3F3C,0x0DA7,0x1C2E,0x6891,0x7918,0x4B83,0x5A0A,
   0x937E,0x82F7,0xB06C,0xA1E5,0xD55A,0xC4D3,0xF648,0xE7C1,
   0x1F36,0x0EBF,0x3C24,0x2DAD,0x5912,0x489B,0x7A00,0x6B89,
   0x83FF,0x9276,0xA0ED,0xB164,0xC5DB,0xD452,0xE6C9,0xF740,
   0x0FB7,0x1E3E,0x2CA5,0x3D2C,0x4993,0x581A,0x6A81,0x7B08,
   0x7470,0x65F9,0x5762,0x46EB,0x3254,0x23DD,0x1146,0x00CF,
   0xF838,0xE9B1,0xDB2A,0xCAA3,0xBE1C,0xAF95,0x9D0E,0x8C87,
   0x64F1,0x7578,0x47E3,0x566A,0x22D5,0x335C,0x01C7,0x104E,
   0xE8B9,0xF930,0xCBAB,0xDA22,0xAE9D,0xBF14,0x8D8F,0x9C06,
   0x5572,0x44FB,0x7660,0x67E9,0x1356,0x02DF,0x3044,0x21CD,
   0xD93A,0xC8B3,0xFA28,0xEBA1,0x9F1E,0x8E97,0xBC0C,0xAD85,
   0x45F3,0x547A,0x66E1,0x7768,0x03D7,0x125E,0x20C5,0x314C,
   0xC9BB,0xD832,0xEAA9,0xFB20,0x8F9F,0x9E16,0xAC8D,0xBD04,
   0x3674,0x27FD,0x1566,0x04EF,0x7050,0x61D9,0x5342,0x42CB,
   0xBA3C,0xABB5,0x992E,0x88A7,0xFC18,0xED91,0xDF0A,0xCE83,
   0x26F5,0x377C,0x05E7,0x146E,0x60D1,0x7158,0x43C3,0x524A,
   0xAABD,0xBB34,0x89AF,0x9826,0xEC99,0xFD10,0xCF8B,0xDE02,
   0x1776,0x06FF,0x3464,0x25ED,0x5152,0x40DB,0x7240,0x63C9,
   0x9B3E,0x8AB7,0xB82C,0xA9A5,0xDD1A,0xCC93,0xFE08,0xEF81,
   0x07F7,0x167E,0x24E5,0x356C,0x41D3,0x505A,0x62C1,0x7348,
   0x8BBF,0x9A36,0xA8AD,0xB924,0xCD9B,0xDC12,0xEE89,0xFF00
   };

int CRCVal=0;
int i=0;
 
for(i=0; i<data.length; i++){
CRCVal = CRCTABLE[(CRCVal ^= ((data[i]) & 0xFF)) & 0xFF] ^ (CRCVal>>8);
}

return Integer.toHexString(CRCVal);
}

    public static String crcTable(byte[] bytes) { 
        int[] table = {
            0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
            0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
            0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
            0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
            0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
            0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
            0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
            0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
            0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
            0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
            0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
            0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
            0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
            0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
            0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
            0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
            0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
            0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
            0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
            0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
            0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
            0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
            0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
            0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
            0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
            0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
            0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
            0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
            0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
            0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
            0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
            0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040,
        };

        int crc = 0x0000;
        
        for (byte b : bytes) {
            crc = (crc >>> 8) ^ table[(crc ^ b) & 0xff];
        }

        return Integer.toHexString(crc);
    }
public static String mkCrc16(byte[] b) {
    	CRC16 crc16 = new CRC16();
    	
    	for (int i = 0; i < b.length; i++){
    	crc16.update(b[i]);
    	}
    	
    	return Integer.toHexString(crc16.value);
    }
    
    public static final String evalCRC16(byte[] data) {
    	int crc = 0xFFFF;
    	
    	for (int i = 0; i < data.length; i++) {
    	crc = (data[i] << 8) ^ crc;
    	
    	for (int j = 0; j < 8; ++j){
    	if ((crc & 0x8000) != 0)
    	crc = (crc << 1) ^ 0x1021;
    	else
    	crc <<= 1;
    	}
    	}

    	return Integer.toHexString((crc ^ 0xFFFF) & 0xFFFF);
    }
    
    private static int parse(char c) {
 if (c >= 'a'){
 return (c - 'a' + 10) & 0x0f;
 }
 
 if (c >= 'A'){
 	return (c - 'A' + 10) & 0x0f;
 }
 
 return (c - '0') & 0x0f;
}
    
    public static byte[] HexString2Bytes(String hexstr) {
byte[] b = new byte[hexstr.length() / 2];          
int j = 0;

for (int i = 0; i < b.length; i++) {
char c0 = hexstr.charAt(j++);
char c1 = hexstr.charAt(j++);

b[i] = (byte) ((parse(c0) << 4) | parse(c1));   
}

return b;
}

    public static void main(String[] args){
    	byte[] test=CRCUtil.HexString2Bytes("05010001");//89A4
    	System.out.println(CRCUtil.mkCrc16(test));
    	System.out.println(CRCUtil.evalCRC16(test));
    	System.out.println(CRCUtil.crcTable(test));
    	System.out.println(CRCUtil.getCRC16(test));
    }
}
